• 대한의용생체공학회:의공학회지
• /
• 제28권2호
• /
• pp.169-173
• /
• 2007

During laser irradiation, mechanically deformed cartilage undergoes a temperature dependent phase transformation resulting in accelerated stress relaxation. Clinically, laser-assisted cartilage reshaping may be used to recreate the underlying cartilaginous framework in structures such as ear, larynx, trachea, and nose. Therefore, research and identification of the biophysical transformations in cartilage accompanying laser heating are valuable to identify critical laser dosimetry and phase transformation of cartilage for many clinical applications. quasi-elastic light scattering was investigated using Ho : YAG laser $(\lambda=2.12{\mu}m\;;\;t_p\sim450{\mu}s)$ and Nd:YAG Laser $(\lambda=1.32{\mu}m\;;\;t_p\sim700{\mu}s)$ for heating sources and He : Ne $(\lambda=632.8nm)$ laser, high-power diode pumped laser $(\lambda=532nm)$, and Ti : $Al_2O_3$ femtosecond laser $(\lambda=850nm)$ for light scattering sources. A spectrometer and infrared radiometric sensor were used to monitor the backscattered light spectrum and transient temperature changes from cartilage following laser irradiation. Analysis of the optical, thermal, and quasi-elastic light scattering properties may indicate internal dynamics of proteoglycan movement within the cartilage framework during laser irradiation.

• Journal of Advanced Marine Engineering and Technology
• /
• 제36권8호
• /
• pp.1010-1015
• /
• 2012

DME는 천연가스로부터 합성할 수 있는 대량의 에너지원이 된다. 한국가스공사는 DME 상업규모의 생산플랜트를 개발하고 이의 국내 공급을 위해 해외 자원 확보를 추진하고 있다. 본 논문은 응력과 변형 해석을 통하여 DME저장탱크의 설계기준을 제공하였고, DME FPSO저장탱크의 증발현상을 파악하기 위하의 증발을 발생시키는 원인인 열유입과 선박의 유동에 따른 증발량 실험을 수행하였다. 실험결과, 롤링의 각도가 커지고 액체 충전량이 많을수록 증발량이 증가하였다. 롤링각도가 15도 일 때의 증발량은 정지상태의 열유입 만에 의한 증발량 보다 약 20%가 증가하였다.

• 한국해양공학회지
• /
• 제15권4호
• /
• pp.28-37
• /
• 2001

The water quality in Yongil Bay is getting worse due to the sewage and the waste water from the surrounding industrial complex. The study aims to simulate the current system that is necessary to build ecosystem model for the optium water quality control and clarify the correlation of current system characteristics with water quality in Yongil Bay. To clarify the characteristics of coastal water movement system and verify the applicability of the 3-D model, the current system was simulated using 3-D model baroclinic model which considers tidal current and density effects. As the results of numerical experiments, it is proved the 3-D model is the most applicable on appearing the current system of the stratificated Yongil Bay difference of density. Form the results of simulation considered tidal current only, it can be clarified that the water body flows in the inner bay through the bottom layer and flows out the outer bay through the surface layer in Yongil Bay. And the fresh water from the Hyongsan river and the thermal discharge form POSCO have a little effect on the current system in Yongil Bay, but the diffusion of heat and salt has an important effect upon the formation of the density stratification of the water quality distribution is closely related with the current structure characteristics as well as the tidal residual current system in Yongil Bay.

• 자원환경지질
• /
• 제23권1호
• /
• pp.81-86
• /
• 1990

Palemagnetic study on the Deadong Super Group in the Mungyong area has been carried out to obtain the direction of NRM and virtual geomagnetic pole(VGP), and to investigate geomagnetic stratigraphy and geotectonic evolution. Twenty eight core specimens from five sites in Dangog and Bongmyongsan Formations yield magnetically stable results by thermal demagnetization test. Mean declination and inclination of Dangog and Bongmyongsan formations are $52.4^{\circ}E$ and $-57.3^{\circ}$, respectively, which indicate reversal polarity. VGP is located at $1.2^{\circ}N$ in latitude and $269.4^{\circ}E$ in longitude, which is quite different from those of other contemporary formations in China. This suggests that the study area has suffered from differnt tectonic movement caused by Daebo Orogeny occurred in the Korean Peninsula during post-Daedong and pre-Kyongsang Systems. As compared VGP of Daedong Super Group in the Mungyong area with wordwide Mesozoic paleomagnetic polarity stratigraphy, it is correlated with the reverse Epoch in the Graham normal interval. This suggests that the time of formations of Dangog and Bongmyongsan is in the age of 190-195 my.

• 한국실내디자인학회논문집
• /
• 제14권5호
• /
• pp.52-61
• /
• 2005

Ecological traces appearing in contemporary architecture are based on modern architecture and most aspects on the contemporary architecture are related with the successive trend or break of the modern architecture. The concept of environment in the modern age has established clear destination, as it has been considered as nature. The architecture under a mechanical world view in the modem age has sustained the opposing connection with nature as environment. However, there have been architects maintaining the sympathy with nature in that vortex. This trend has been regarded as same context as ecological architecture and estimated to the outpost of ecological characteristics appearing in the contemporary architecture. This study is to make it clear that the ecological manifestation in the contemporary architecture is based on the ecology in the modem architecture through considering ecological ideals of architects in the modern architecture and considering space composition and structural properties in the modern architecture of ecological paradigm. The scope of this study contains spacial analysis, design strategy, and design types of organic architecture in nature, which has appeared from the modern age. First, the division into period is carried out according to the organic tendency of non-mainstream in the modern architecture: Arts and Crafts Movement, Art Nouveau, Sezession, Expressionism, Organic Architecture, Regionalism, Internationalism. Therefore, this study is significant to be on the search for a start to suggest ecological point of view to architectural space in modern architecture and is search organic characteristics for ecological characteristics in modern architecture; organic relation, thermal buffer space, regionalism, multi-layer, energy efficiency.

• Coupled systems mechanics
• /
• 제6권2호
• /
• pp.113-125
• /
• 2017

This paper proposes the idea to enhance the heat transfer in Gas Tungsten Arc Welding (GTAW) by using the azimuthal magnetic field. The azimuthal magnetic field generated by the external currents makes the Lorentz force stronger, and consequently improves the heat transfer by the faster flow movement. The enhanced heat transfer might improve the welding performance by increasing the temperature at the workpiece. To validate the proposed idea, a two-dimensional axi-symmetric model of GTAW is built, and the multiphysics simulation of GTAW is carried out. As the analysis result, the distributions of electric current, electromagnetic fields, arc flow velocity, and temperature are investigated. Then, the proposed idea for heat transfer enhancement is validated by comparing the Lorentz force, flow velocity, and temperature distribution with and without azimuthal magnetic fields.

• Journal of Construction Engineering and Project Management
• /
• 제6권2호
• /
• pp.30-39
• /
• 2016

This research presents the development of a self-governing mobile robot navigation system for indoor construction applications. This self-governing robot navigation system integrated robot control units, various positioning techniques including a dead-reckoning system, a UWB platform and motion sensors, with a BIM path planner solution. Various algorithms and error correction methods have been tested for all the employed sensors and other components to improve the positioning and navigation capability of the system. The research demonstrated that the path planner utilizing a BIM model as a navigation site map could effectively extract an efficient path for the robot, and could be executed in a real-time application for construction environments. Several navigation strategies with a mobile robot were tested with various combinations of localization sensors including wheel encoders, sonar/infrared/thermal proximity sensors, motion sensors, a digital compass, and UWB. The system successfully demonstrated the ability to plan an efficient path for robot's movement and properly navigate through the planned path to reach the specified destination in a complex indoor construction site. The findings can be adopted to several potential construction or manufacturing applications such as robotic material delivery, inspection, and onsite security.

• E2M - 전기 전자와 첨단 소재
• /
• 제8권1호
• /
• pp.71-76
• /
• 1995

The thermal oxidation of Ge$_{0.2}$Si$_{0.8}$ in wet ambient has been investigated by Rutherford Backscattering Spectrometry(RBS). A uniform Ge$_{0.2}$Si$_{0.8}$O$_{2}$ oxide is formed at temperatures below 650.deg. C for polycrystalline and below 700.deg. C for single crystalline substrates. At higher temperatures Ge becomes depleted from the oxide and finally SiO$_{2}$ oxide is formed with Ge piled-ub behind it. The transition between the different oxide types depends also on the crystallinity of Ge$_{0.2}$Si$_{0.8}$. When a uniform Ge$_{0.2}$Si$_{0}$8/O$_{2}$ oxide grows, its thickness is proportional to the square root of the oxidation time, which suggests that the rate noting process is the diffusive transport of oxidant across the oxide. It is believed the oxidation is controlled by the competition between the diffusion of Ge or Si in Ge$_{0.2}$Si$_{0.8}$ and the movement of oxidation front.t.oxidation front.t.

• Journal of Advanced Marine Engineering and Technology
• /
• 제28권7호
• /
• pp.1055-1062
• /
• 2004

As for the Production of internal combustion engines there has been further movement toward development of high Performance engines with improved fuel efficiency as well as a lightweight and a small size. These tendencies help to solve the problems in engines for example, such as thermal load. abnormal combustion and so on. In order to investigate these Problems, a thin film-type probe for measuring instantaneous temperature has been suggested. A method for manufacturing such a probe was established in this study The instantaneous surface temperature of a constant volume combustion chamber was measured by using this probe and the heat flux was obtained through Fourier analysis In order to thoroughly understand the characteristics of combustion. authors measured wall temperature of combustion chamber and calculated heat flux through a cylinder wall while varying the protrusion height of probe. For these Purposes, the instantaneous surface temperature probe was developed. thereby making possible the analysis of instantaneous temperature of wall surface and the detection of unsteady heat flux in the constant volume combustion chamber.

• 한국가시화정보학회:학술대회논문집
• /
• 한국가시화정보학회 2007년도 추계학술대회
• /
• pp.128-133
• /
• 2007

An electrostatic inkjet head can be used for manufacturing processes of large display systems and printed circuit boards (PCB) as well as inkjet printers because an electrostatic field provides an external force which can be manipulated to control sizes of droplets. The existing printing methods such as thermal bubble and piezo inkjet heads have shown difficulties to control the ejection of the droplets for printing applications. Thus, the new inkjet head has been proposed using the electrostatic force. A numerical analysis has been performed to calculate the intensity of the electrostatic field using the Maxwell's equation. Also, experiments have been carried out to investigate the droplet movement using a downward capillary with outside diameter of $500{\mu}m$. Gravity, surface tension, and electrostatic force have been analyzed with high voltages for a drop-on-demand ejection. It has been observed that the droplet size decreases and the frequency of the droplet formation and the velocity of the droplet ejection increase with increasing the intensity of the electrostatic field using high-speed camera.